Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!texbell!texsun!newstop!sun!pepper!cmcmanis
From: cmcmanis%pepper@Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga
Subject: Re: Clipboard support, and why it hasn't happened.
Message-ID: <125872@sun.Eng.Sun.COM>
Date: 5 Oct 89 18:22:19 GMT
References: <4272@sugar.hackercorp.com> <4998@cbnewsm.ATT.COM>
Sender: news@sun.Eng.Sun.COM
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 40

>In article <4272@sugar.hackercorp.com> (Peter da Silva) writes (I think):
>>	* It must be no harder to use the clipboard than it is to use
>>	  a file. ... That way you could open CLIPBOARD:0, write stuff,
>>	  and close it with no more difficulty than you have now creating
>>	  a file in RAM:.

[Peter: See Andy Finkel's clip.handler on the DevCon II disks. It sets up
the device CLIPS: which is almost like a file]

In article <4998@cbnewsm.ATT.COM> (Neil Weinstock) responds:
>I'll bite.  How is this any different from using RAM in the first place?

[A little context for a comment :-)]

The Clipboard started out with a vision as far as I can tell. And that
vision was "Universal place to put objects of indeterminate structure."
The only flaw in the vision that I could see was that it counted on
people being able to understand IFF and that was (and is) a big bottleneck
for a lot of people. Back at the earliest DevCon's and talks at BADGE
the vision was "... you write this thing onto the clipboard in a form
that application X understands, and when you paste it, it appears in a 
form that application Y understands." So if you clipped a SMUS track 
from a music program and pasted it into a music notator it would come
out as sheet music. I'm not sure what would happen if it was pasted to
NotePad. (Probably appear as a bunch-o-notes. :-)) This differs significantly
from RAM: in that the files there are free form and if they aren't text
your application may not understand them, and may not _know_ that it doesn't
understand them. It's a good vision and the iff.library will help because
it specifically allows you to talk to the clipboard (and avoid the problems
of seeking backwards and such.) What it doesn't provide is the other half
of what is required which is "Given a FORM xxxx on the clipboard, and that
I understand FORM yyyy, find me a conversion routine that will translate from
one to the other." For some, like 8SVX -> ILBM it should be pretty easy 
(the PLPLOT stuff would do it nicely) but others like ILBM->8SVX or 
ANIM->FTXT are less easily specified. 

--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.
"If I were driving a Macintosh, I'd have to stop before I could turn the wheel."